The field of the invention is pushback cart storage systems. Pushback cart storage systems are typically used in warehouses and other storage facilities to efficiently store loaded pallets. Pushback cart storage systems typically include rolling carts for supporting pallets. The carts include wheels that roll along rails on storage racks or frames, and/or along tracks in other carts. The rails are preferably slightly inclined so that gravity assists in moving the carts forward along the rails to the front of the rack. A storage rack may include several levels of inclined rails for storing several pallets vertically.
By providing one or more rolling carts on a set of rails, pallets may be loaded onto carts and pushed back along the rails toward the rear of the storage rack. In this manner, pallets may be stored one in front of the other on the storage rack, and several pallets may be loaded and unloaded from a single aisle. As a result, the number of aisles required for forklifts to maneuver throughout a warehouse is minimized, and the usable space between aisles is therefore increased. Accordingly, aisle space required for forklift access when using conventional storage rack systems may instead be used for additional pallet storage racks, thus providing more efficient use of space.
Various pushback cart storage systems have been successfully used in the past, as described, for example, in U.S. Pat. Nos. 6,129,223, 5,415,300, and 5,598,934, incorporated herein by reference. While these systems have been effective, there is a need for improved designs that reduce overall system cost and increase storage efficiency.